// abstract修饰的类不能被实例化只能继承
abstract class person {
	name: string = '孙悟空';
	age: number = 18;
    // 定义一个抽象方法让子类去实现
	abstract say(): void;
}

class wgy extends person {
	say(): void {
		console.log('我是子类重写方法');
	}
}
